1. Field of Invention
The present invention relates to an electrostatic spinning apparatus. More particularly, the present invention relates to an electrostatic spinning apparatus for mass production.
2. Description of Related Art
Electrostatic spinning technology can be used for manufacturing nanofibers. The principle of electrostatic spinning technology is to provide a driving force generated by an electric field between a positive electrode and a negative electrode, so as to overcome surface tension and viscosity of the polymeric electrostatic spinning solution. In addition, fibers made by electrostatic spinning solution and spun from a spinneret repel each other because they are like-charged; when solvent evaporates, ultra-thin fibers can be formed. Comparing to the fibers produced by prior spinning technology, the fabric made by electrostatic spinning method is featured by several properties, such as higher porosity, larger surface area, and smaller pore size than those of conventional fabrics.
The charged electrostatic spinning solution is spun to a collecting electrode from the spinneret. However, the aperture of the spinneret is very small and is easily blocked up by residual solution inside the spinneret. Moreover, the spinneret and pipe need to be cleaned when changing electrostatic spinning solution. The applicability of the electrostatic spinning technique and the diversity of electrostatic spinning solutions are thus reduced.
WO patent 2005/024101A1 provides a roller as a high voltage electrode to spin the electrostatic spinning solution without the spinneret. The roller in a solution tank needs to be machined to form a raised portion on the surface of the roller. The electrostatic spinning solution is departed from the raised portion of the roller and formed the electrostatic spinning fibers on the collecting electrode. The method requires an additional process of machining roller surface, so the cost of the electrostatic spinning apparatus is increased.